Computer network server system and related components are typically housed in racks configured to house and to assimilate the functions of a plurality of component devices. System racks provide efficient organization for the plurality of components for ease of access, serviceability, expandability, power distribution, cooling, etc.
These system racks generally are housed in a computer server room, which hosts many computers and servers that all require fans to keep the systems cooled. Cooling fans could come with the systems and are part of the systems. Alternatively, cooling fans could also be installed outside the systems. When cooling fans are installed outside systems, typically, they are installed in the same system racks with the systems they are designed to cool. Cooling fans emit noise (or acoustic waves) with varying wavelengths (or frequency) and intensities (or magnitudes), depending on the fan models and the running speeds. Multiple cooling fans in a computer server room running at one time may create excessive ambient noise. The ambient noise can be a high-pitched sound that sometimes prevents personnel working in the computer server room from concentrating on their work or even talking to each other. The ambient noise can grow to the point that personnel working in the room are unable to be productive.
To quiet the cooling fan noise, sound absorbing materials, such as acoustical foams, have been used in the design and construction of computer server rooms. Although acoustical foams reduce ambient noise, they do not completely remove ambient noise. In addition, acoustical foams can be quite expensive and are not practical to some computer server rooms, due to fire safety requirements or other reasons.
In consideration of the foregoing, what is needed is an efficient noise reduction apparatus and method to increase effectiveness of cooling fan noise control in computer server rooms with multiple computers, servers and cooling fans.